/in/foo.cc: In function 'int main()':
/in/foo.cc:18:13: warning: unused variable 'i' [-Wunused-variable]
   18 |         int i=0;
      |             ^
/in/foo.cc:19:17: warning: 'i' may be used uninitialized [-Wmaybe-uninitialized]
   19 |         for(int i;i<na;i++)
      |                 ^